AP Biology Practice Test #5 These are examples of the kinds of objective questions that may be used on the AP Biology exam. This is not an example of a complete examination. 1. Which of the following best describes an intimate ecological association in which an organism benefits from living on or within a host, but which generally has a negative effect on the host? a)mutualism b)saprophytism c)commensalism d)parasitism e) predation 2. While studying the cell with the electron microscope, a scientist notes the following: numerous ribosomes, a well-developed endoplasmic reticulum, chloroplasts, and a cell wall. Which of the following could be the source of this cell? a) a fungus b)an animal c)a bacterium d)a plant e)a virus 3. Which of the following statements best summarizes organic evolution as it is viewed by moder evolutionists? a) it is goal directed. b) it represents the results of selection for acquired characteristics. c) it is synonymous with the process of gene flow. d) it is the descent of humans from the present-day great apes. e) it is the differential survival and reproduction of certain phenotypes. 4. If a segment of DNA is 5'-TAC GAT TAG-3', the RNA that results from the transcription of this segment will be a) 3'-TAC GAT TAU-5' c) 3'-UAC GAU UAG-5' e)3'-AUG CUA AUC-5' b) 3'-ATG CTA ATA-5' d) 3'-AAC GAU UAA-5' 5. The bones of a human arm are homologous to structures in all of the following except a a)whale flipper b)bat wing c)butterfly wing d)bird wing e)frog forelimb 6. The ancestors of land plants most likely resembled modern day members of the a)Cyanobacteria (blue-green algae) d)Phaeophyta (brown algae) b) Rhodophyta (red algae) e)Chrysophyta (diatoms and golden-brown algae c)Chlorophyta (green algae) 7. Which of the following offers the best description of neural transmission across a mammalian synaptic gap? (a) Neural impulses involve the flow of K' and Na' across the gap. (b) Neural impulses travel across the gap as electrical currents. (c) Neural impulses cause the release of chemicals that diffuse across the gap. (d) Neural impulses travel across the gap in both directions. (e) The calcium within the axons and dendrites of nerves adjacent to a synapse acts as the neurotransmitter. 8. Which of the following statements is true about the Krebs (citric acid) cycle and the Calvin (lightindependent) cycle? (a) They both result in a net production of ATP and NADH. (b) They both require a net input of ATP. (c) They both result in a release of oxygen. (d) They both take place within the cytoplasmic matrix. (e) They both are carried out by enzymes located within an organelle matrix. 9. Two fossil vertebrates, each representing a different class, are found in the undisturbed rock layers of a cliff. One fossil is a representative of the earliest amphibians. The other fossil, found in an older rock layer below the amphibian, is most likely to be (a) a dinosaur (b) a fish (c)an insectivorous mammal (d) a snake (e) a bird 10. Regarding mitosis and cytokinesis, one difference between higher plants and animals is that in plants a)the spindles contain cellulose microfibril in addition to microtubules, whereas animal spindles do not contain microfibrils. b)sister chromatids are identical, whereas in animals they differ from one another. c)a cell plate begins to form at telophase, whereas in animals a cleavage furrow is initiated at that stage. d)chromosomes become attached to the spindle at prohpase, whereas in animals chromosomes do not become attacked until anaphase. e)spindle poles contain centrioles, whereas spindle poles in animals do not 11. A common feature of starch and glycogen is that moleules of both a)form microfibrils that give support to connective tissue fibers. b)contain repeated monomers of glucose and galactose. c)are important structural components of plant cell walls. d)are polymers of glucose. e)are water-soluble disaccharides. 12. This biome exhibits the greatest diversity in plant species. a)grassland b)taiga c)deciduous forest d)tundra e)tropical rain forest 13. In this biome, agriculture is commonly practiced in a "cut-burn-cultivate-abandon" mode. a)grassland b)taiga c)deciduous forest d)tundra e)tropical rain forest 14. This biome can be recognized by its coniferous forests and relatively infertile, acidic soil. a)grassland b)taiga c)deciduous forest d)tundra e)tropical rain forest 15. The bonding of two amino acid molecules to form a larger molecule requires (a) the release of a water molecule (b) the release of a carbon dioxide molecule (c) the addition of a nitrogen atom (d) the addition of a water molecule (e) an increase in activation energy 16. If young male zebra finches are raised by foster parents of another species, the Bengalese finch, they will court female Bengalese finches instead of females of their own species. This behavior results from which of the following? a) Imprinting b) Habituation c) Conditioning d) Reinforcement e) Pheromones 17. The relative location of four genes on a chromosome can be mapped from the following data on crossover frequencies G Frequency of Crossover B and D 5% C and A 15% A and B 30% C and B 45% C and D 50% Which of the following represents the relative positions of these four genes on the chromosome? (a) ABCD (b) ADCB (c) CABD (d) CBAD (e) DBCA 18. When hydrogen ions are pumped out of the mitochondrial matrix, across the inner mitochondrial membrane, and into the space between the inner and outer membranes, the result is (a) damage to the mitotochondrion (b) the reduction of NAD (c) the restoration of the Na-K balance across the membrane (d) the creation of a proton gradient (e) the lowering of pH in the mictochondrial matrx 19. Once transcribed, eukaryotic MRNA typically undergoes substantial alteration that results primarily from (a) excision of introns (b) fusion into circular forms known as plasmids (c) linkage to histone molecules (d) union with ribosomes (e) fusion with other newly transcribed MRNA molecules to form larger translatable units 20. The function of water in photosynthesis is to (a) combine With C02 (b) absorb light energy (c) supply electrons in the light-dependent reactions (d) transport H, ions in the light-independent (dark) reactions (e) Provide 02 for the light-independent (dark) reactions A large population of laboratory animals has been allowed to breed randomly for a number of generations. After several generations, 49 percent of the animals display a recessive trait (bb), the same percentage as at the beginning Of the breeding program. The rest of the animals show the dominant phenotype, with heterozygotes indistinguishable from the homozygous dominants. 21. What is the most reasonable conclusion that can be drawn from the fact that the frequency of allele b has not changed over time? (a) The Population is undergoing genetic drift. (b) The two phenotypes are equally adaptive under laboratory conditions. (c) The genotype BB is lethal. (d) There has been a high rate of mutation of aliele B to allele b. (e) There has been sexual selection favoring allele b. 22. What is the frequency of allele b in the gene pool? (A) 0.70 (B) 0.51 (C) 0.49 (D) 0.30 (E) 0.07 23. What proportion of the Population is heterozygous (Bb) for this trait? (A) 0.51 (B) 0. 42 (c) 0.21 (D) 0. 09 (E) 0.07 1. D 2. D 3. B 4. E 5. C 6. C 7. C 8. E 9. B 10. C 11. D 12. E 13. A 14. B 15. A 16. A 17. C 18. D 19. A 20. C 21. B 22. A 23. B